Rod clip and apparatus

ABSTRACT

A clip is disclosed which can be used to fabricate the lattice structure of reinforcing rods of the type used in the construction of steel rod reinforced concrete slabs. An apparatus to fasten those clips in position is also disclosed The preferred clip ( 1 ) has a substantially rectangular body ( 2 ). A recess ( 3 ) extends from a first face ( 4 ) of the body ( 2 ) towards an opposite face ( 5 ). The recess ( 3 ) terminates in an arcuate portion ( 6 ). The inner edges ( 7   a, b ) of the recess ( 3 ) are convergent towards the arcuate portion ( 6 ). The apparatus has an aperture ( 13 ) in a base plate ( 12 ). Stops ( 18   a, b, c ) on the plate ( 12 ) suitably position the apparatus whereupon a shearing plate ( 32 ) can shear a clip ( 1 ) from a stack of such clips to pass through the aperture ( 13 ) wherein the arcuate portion ( 6 ) of the clip ( 1 ) engages the upper rod ( 16 ). A pair of pivoting J-shaped arms ( 21   a, b ) are then actuated which bend the lower portions of the clip ( 1 ) around the lower rod ( 17 ) securing the two rods ( 16, 17 ) together.

This invention relates to fastening. In particular, it is directed to afastening clip and an apparatus for use with that clip, the clip beingused to fasten together crossing elongate members and has a specific,but not limiting, use to secure the lattice type structure ofreinforcing rods of the type used in the construction of steel rodreinforced concrete slabs.

Concrete slabs as used in the foundation for a building or as asuspended ceiling or floor incorporate an open lattice or grid of steelrods for strength. To prevent these rods from sagging under the weightof the wet concrete until it has set, the rods are tied together. It isusual to secure each rod to each other rod that crosses it along itslength. The usual securing method is, at each such intersection, to wrapa short length of wire around both rods and then tightly twist the endsto secure the rods in place. These wire tying operations are usuallyundertaken manually using some form of gripping device to twist thewire.

Even in relatively small constructions, the time taken to fabricate thereinforced steel lattice is significant adding noticeably to the overallcost of the building construction. Further disadvantages include (1)operator fatigue due to the large number of ties to be performed, thuseffectively reducing the rate of tying and actually adding to the timeand therefore cost of completing the construction; (2) muscular andrelated problems for the operator as the operator must bend over and/orsquat in order to effect the tie; (3) tying is not uniform beingdependent upon the efficiency of the operator, thus potentially leadingto the aforementioned sagging of the rods before the concrete sets.Also, after the tie is made, the excess wire length is cut resulting insmall lengths of wire which tend to settle to the base of the wetconcrete slab. When this slab is a suspended floor, these wire remnantsare visible on an exposed surface where they oxidise leading tounsightly rust stains. More time is thus consumed in removing thesesmall fragments of wire.

One prior attempt to alleviate such disadvantages is to secure the rodstogether by welding. However, welding of such load bearing structures isbanned in some countries as it may alter the temper and thus strength ofthe metal in and adjacent to the weld zones. Other disadvantages include(1) operators are exposed to the noxious welding gases and must havefrequent periodic medical checks; (2) there is a wastage of material ifa mistake is made as a weld cannot be reversed; (3) the welding flame,because of the potential damage that it can inflict to an unshieldedeye, must be screened from passers-by; and (4) it still fails toalleviate the muscle fatigue of the operator.

Another prior art attempt to overcome these disadvantages is disclosedin U.S. Pat. No. 3,169,559 wherein a tool is described whichautomatically twists the ends of a substantially U-shaped clip placed onthe two crossing members. However, this tool is only of limited use asthe tool head must pass through the gaps of the lattice work to functionthus preventing its use on close-knit lattice work. Further, the clipsare placed diagonally on the cross members leading to poor stabilitybecause of the reduced contact between the clip and rod. Anotherdisadvantage is that the tool twists but does not sever the dip endsthus requiring a second separate cutting action to complete thefastening process.

Yet another prior art attempt to resolve at least some of thesedisadvantages is described in U.S. Pat. No. 4,653,548 and its Australianequivalent 574043 whereby the ends of two arms of a wire clip can betwisted and the ends severed as the final phase of the fastening.However, this solution still requires two distinct manual operations,the first is the positioning of the clip where required and the secondis the actual engagement of the clip with the tool. The cut ends arealso still not contained and therefore have to be removed in a thirdoperation if necessary.

It should also be noted that all of these prior art attempts are onlyapplicable to the use of a wire which can only provide limited strengthcapabilities.

It is thus a general object of the present invention to overcome, or atleast ameliorate, one or more of the above-mentioned disadvantages.

According to a first aspect of the present invention, there is provideda clip for use in the fastening together of two crossing substantiallyelongate upper and lower members, said dip including a body with arecess extending from a first face to near a second face substantiallyopposite said first face to form a first arm and a second arm, saidrecess terminating with a shaped portion of a configurationsubstantially complementary to the exterior surface of said upper memberwherein, when said clip is in a fastened position, said recess canengage said upper member and said first arm and said second arm canengage said lower member sufficient to fasten said upper member and saidlower member together.

Preferably, said body is substantially polygonal in elevation.

Preferably, said polygonal elevation is rectangular.

Preferably, said shaped portion is substantially arcuate in elevation.

Preferably, said recess converges from said first face to near saidsecond face.

According to a second aspect of the present invention, there is providedan apparatus to install a clip as hereinbefore described, said apparatusincluding

a base plate which has an aperture through which an intersection of asaid upper member with a said lower member can be viewed;

retaining means to retain at least one of said clip;

positioning means to enable a said clip to be released from saidretaining means and pass through said aperture to be positioned on saidupper member at said intersection; and

securing means to secure said first arm and said second arm to saidlower member when a said clip has been positioned at said intersection.

Preferably, said base includes a locating means to assist in locatingsaid apparatus at a required said intersection.

More preferably, said retaining means retains a plurality of said clip.

Preferably, said positioning means includes a shearing means adapted toshear sequentially a series of said clip from said retaining means.

Preferably, said securing means includes a first lever which can engageand bend said first arm to engage said lower member and a second leverwhich can engage and bend said second arm to engage said lower member,engagement of said first and second arm with said lower member beingsufficient to fasten together said lower member and said upper member.

Preferably, said apparatus includes a handle from which said positioningmeans and said securing means can be operated.

In a first embodiment of the apparatus of the present invention,positioning of said clip and subsequent engagement of said first arm andsaid second arm with said lower member is undertaken mechanically.

In a second embodiment of the apparatus of the present invention,positioning of said clip and subsequent engagement of said first arm andsaid second arm with said lower member is undertaken hydraulically.

In a third embodiment of the apparatus of the present invention, theoperation of the apparatus can be undertaken electrically,electronically or by gas power.

As a third aspect of the present invention, there is provided a methodof fastening together two crossing substantially elongate upper andlower members wherein a clip as hereinbefore described is secured at anintersection of said lower and upper member using an apparatus ashereinbefore described.

A fourth aspect of the present invention is the provision of alattice-type arrangement comprising a series of crossing lower and uppermembers wherein each intersection of said upper and lower member hasbeen fastened with a clip as hereinbefore described.

Preferred embodiments of the present invention will now be describedwith reference to the accompanying drawings, wherein:

FIG. 1 illustrates a first embodiment of a clip constructed inaccordance with the present invention;

FIG. 2 illustrates a second embodiment of a clip constructed inaccordance with the present invention;

FIG. 3 is an upper perspective sketch of an apparatus constructed inaccordance with the present invention;

FIG. 4 is an enlargement of the area A of the apparatus of FIG. 3; and

FIG. 5 is a lower perspective sketch of the apparatus of FIG. 3.

Referring first to FIG. 1, a clip (1) comprises a substantiallyrectangular body (2). A recess (3) extends from a first face (4) of thebody (2) towards an opposite face (5). The recess (3) terminates in anarcuate portion (6). The inner edges (7 a,b) of the recess (3) areconvergent towards the arcuate portion (6).

In the second embodiment depicted in FIG. 2, the clip (8) is an elongatemember of essentially circular cross section bent in the form of a V toprovide two divergent arms (9 a,b). The closed end (10) of the clip (8)is arcuate.

The apparatus (11) depicted in FIGS. 3-5 comprises a base plate (12)which includes a first rectangular aperture (13). The aperture (13) isof dimensions sufficient to enable an operator of the apparatus (11) toview the intersection (15) of a first upper steel rod (16) and a secondlower steel rod (17) (FIG. 5) and also to allow a clip (1) to passtherethrough. A pair of stops (18 a,b) are affixed to the lower surfaceof the plate (12) which can abut the lower rod (17). A third stop (18 c)is also affixed to the lower surface of the plate (12) to abut the upperrod (16). When the stops (18 a,b,c) are in their respective engagementwith the upper and lower rods (16, 17), the intersection (15) ispositioned substantially centrally within the aperture (13) and in thecorrect position for subsequent use of the apparatus. A handle (19) isaffixed to the upper surface of the plate (12) by any convenient bracket(not illustrated). Supported on the plate (12) are a plurality clips (1)contained within a magazine (20). The clips (1) may be taped orotherwise adhered together for stability within the magazine (20). Aslot (27), of sufficient dimensions to allow a clip (1) to pass through,is present near the front (28) of the magazine (20). A biasing spring(29) or similar is retained within the magazine which can bias theremaining clips (1) in the magazine to the front (28) as each clip (1)is discharged through the slot (27). A cover (30) is pivotally connectedat the rear end (31) of the magazine (20) and incorporates a shearingplate (32) at the front (28) of the cover (30). The cover (30), in itsrest state, is biased upwards to allow the shearing plate (32) to bepositioned above the next clip (1) to be discharged from the magazine(20) through the slot (27). The pivoting cover (30) is connected to anactuator (not illustrated) which can be operated by a two stage switch(33) on the handle (19) by any convenient means known in the art. Afirst J-shaped arm (21 a) has its curved end (22 a) passing through asecond aperture (23 a) in the base plate (12). A second J-shaped arm (21b) has its curved end (22 b) passing through a third aperture (23 b) inthe base plate (12). The other ends (24 a,b) of the two J-shaped arms(21 a,b) are connected together by, and can pivot about, a common arm(39) affixed to the plate (12). The ends (24 a,b) are further connectedto a second common arm (25) which, in turn, is connected to a hydraulicactuator (26) which can pull the arms (21 a,b) in the direction B uponactuation and which allows the arms (21 a,b) to move in the direction B′upon de-actuation thus returning the arms (21 a,b) to their originalposition. The actuator (26) is also operated by the two stage switch(33) on the handle (19) by any convenient means known in the art.

In use, a series of first elongate steel rods (16) and second elongatesteel rods (17) are positioned to form a lattice-like arrangement wellknown in the art of forming a steel reinforced concrete slab. Theapparatus (11) is positioned near the vicinity of an intersection (15)and its position is adjusted until the stops (18 a,b,c) engage therespective upper (16) and lower (17) rods, thus positioning theintersection (15) essentially centrally within the aperture (13).Setting the switch (33) to its first operative stage biases the cover(30) of the magazine (20) downwards, causing the shearing plate (32) tobear upon the upper surface of a clip (1) and shearing that clip (1)from the front of the stack pushing the clip (1) through the aperture(13) where the internal edges of the arcuate portion (6) of the clip (1)engage the upper surface of the upper rod (16) and the internal edges (7a,b) of the recess (6) straddle the upper rod (16) and engage the lowerrod (17). The cover (30) returns to its original rest position and thebiasing spring (29) biases the remaining stack of clips (1) to bringanother clip under the shearing plate (32). Moving the switch (33) toits subsequent second operative stage engages the actuator (26) causingthe J-shaped arms (21 a,b) to move in the direction B simultaneouslybending the lower regions of the arms (21 a,b) around the lower rod (17)thus securing the two rods (16,17) together. Returning the switch (33)to its original rest position disengages the actuator (26) causing theJ-shaped arms (21 a,b) to return to their original positions. Theapparatus (11) can then be moved to a next intersection (15) to repeatthe fastening process.

A similar process operates when the second embodiment of the clip asillustrated in FIG. 2 is used. In this embodiment, the closed end (10)of the clip (8) rests on the upper rod (16) and the arms (9 a,b) aredrawn around the lower rod (17) by the J-shaped arms (21 a,b).

In both embodiments, the clips (1) are of dimensions such that therespective closed ends (6, 10) rest on the upper rod (16) between thestrengthening ridges that are usually present on such reinforcing rods.

By using the present invention, a number of advantages are offeredincluding (a) it is not necessary to restrict the clips to a wire likeconfiguration; clips of a more substantial weight offering a greaterpurchase on the members can be used leading to a more secure fastening;(b) the handle can easily be constructed of a length, adjustable ifrequired, to enable the operator to remain in an upright position; (c)positioning and subsequently fastening of the clip can be undertaken ina single operation; and (d) no cutting of the clip is required afterfastening.

It will be appreciated that the above described embodiments are onlyexemplification of the various aspects of the present invention and thatmodifications and alterations can be made thereto without departing fromthe inventive concept as defined in the following claims.

What is claimed is:
 1. A clip for use in the fastening together of twocrossing substantially elongate upper and tower members, said clipincluding a substantially planar body with a recess extending from afirst face to near a second face substantially opposite said first faceto form a first arm and a second arm, said recess terminating with ashaped portion of a configuration substantially complementary to theexterior surface of said upper member, said clip being adapted suchthat, when said clip is in a fastening position, said recess can engagesaid upper member and said first arm and said second am can each beconformed to a configuration substantially identical to the exteriorsurface of said lower member sufficient to engage with said lower memberto fasten said upper member and said lower member together.
 2. A clip asdefined in claim 1 wherein said body is substantially polygonal inelevation.
 3. A clip as defined in claim 2 wherein said polygonalelevation is rectangular.
 4. A clip as defined in claim 1 wherein saidshaped portion is substantially arcuate in elevation.
 5. A clip asdefined in claim 1 wherein said recess converges from said first face tonear said second face.
 6. An apparatus to install a clip as defined inclaim 1, said apparatus including: (a) a base plate having an aperturethrough which an intersection of a said upper member with a said lowermember can be viewed; (b) retaining means to retain at least one of saidclip; (c) positioning means to enable a said clip to be released fromsaid retaining means and pass through said aperture to be positioned onsaid upper member at said intersection; and (d) securing means to securesaid first arm and said second arm to said lower member when a said cliphas been positioned at said intersection.
 7. An apparatus as defined inclaim 6 wherein said base includes a locating means to assist inlocating said apparatus at a required said intersection.
 8. An apparatusas defined in claim 6 and further including a handle from which saidpositioning means and said securing means can be operated.
 9. Anapparatus as defined in claim 6 wherein said retaining means retains aplurality of said clip.
 10. An apparatus as defined in claim 6 whereinsaid positioning means includes a shearing means adapted to shearsequentially a series of said clip from said retaining means.
 11. Anapparatus as defined in claim 6 wherein said securing means includes afirst lever which can engage and bend said first arm to engage saidlower member and a second lever which can engage and bend said secondarm to engage said lower member, engagement of said first and second armwith said lower member being sufficient to fasten together said lowermember and said upper member.
 12. An apparatus as defined in claim 6wherein positioning of said clip and subsequent engagement of said firstarm and said second arm with said lower member is undertakenmechanically.
 13. A method of fastening together two crossingsubstantially elongate upper and lower members, said method comprising:(a) aligning said members within an apparatus as defined in claim 6,such that said upper member is in contact with, and positionedperpendicularly to, said lower member to form an intersection at whichsaid members are to be fastened together; and (b) securing a clip heldwithin said apparatus at said an intersection of said lower and uppermembers using said apparatus, wherein said clip includes a substantiallyplanar body with a recess extending from a first face to near a secondface substantially opposite said first face to form a first arm and asecond arm, said recess terminating with a shaped portion of aconfiguration substantially complementary to an exterior surface of saidupper member, said clip being adapted such that, when said clip is in afastening position, said recess can engage said upper member and saidfirst arm and said second am can each be conformed to a configurationsubstantially identical to an exterior surface of said lower membersufficient to engage with said lower member to fasten said upper memberand said lower member together.
 14. A lattice-type arrangementcomprising a series of crossing lower and upper members wherein eachintersection of said upper and lower member has been fastened with aclip, said clip including: a substantially planar body with a recessextending from a first face to near a second face substantially oppositesaid first face to form a first arm and a second arm, said recessterminating with a shaped portion of a configuration substantiallycomplementary to the exterior surface of said upper member, said clipbeing adapted such that, when said clip is in a fastening position, saidrecess can engage said upper member and said first arm and said secondam can each be conformed to a configuration substantially identical tothe exterior surface of said lower member sufficient to engage with saidlower member to fasten said upper member and said lower member together.